阅读说明：本技术 一种钒掺杂单晶氧化钨电致变色和储能材料及制备方法 (Vanadium-doped single-crystal tungsten oxide electrochromism and energy storage material and preparation method thereof ) 是由 张勇 董森宇 吴玉程 陶新宇 张雪茹 舒霞 王岩 崔接武 秦永强 于 2021-08-18 设计创作，主要内容包括：本发明公开了一种钒掺杂单晶氧化钨电致变色和储能材料,具有多孔单晶纳米线结构,纳米棒直径为15-40nm,纳米线定向生长。本发明还公开了一种钒掺杂单晶氧化钨电致变色和储能材料的制备方法,以磁控溅射的氧化钨纳米颗粒为仔晶层,结合水热法定向生长获得钒掺杂密排六方结构氧化钨纳米线,本发明的纳米线以仔晶层为形核生长点沿着密排六方三氧化钨的c轴定向生长获得多孔单晶纳米线阵列,钒均匀掺杂在纳米线中,钒的掺杂引起晶面间距增大和并提高了氧空位含量,形成钒氧键,获得了优异的电致变色和储能双功能性能,可以在不同电压下实现透明和深蓝色的迅速转变,并对应电量的储存和释放,具有较大的面电容和良好的循环稳定性和倍率性能。(The invention discloses a vanadium-doped monocrystalline tungsten oxide electrochromic energy storage material which has a porous monocrystalline nanowire structure, wherein the diameter of a nanorod is 15-40nm, and the nanowire grows directionally. The invention also discloses a preparation method of the vanadium-doped single-crystal tungsten oxide electrochromic and energy storage material, wherein magnetron-sputtered tungsten oxide nano particles are used as seed crystal layers, and the vanadium-doped tungsten oxide nano wires with a close-packed hexagonal structure are obtained by combining the oriented growth of a hydrothermal method.)

1. The electrochromic and energy storage material is characterized by having a porous single crystal nanowire structure, wherein the diameter of a nanorod is 15-40nm, the nanowire grows directionally, and vanadium is uniformly doped in the nanowire.

2. The vanadium-doped monocrystalline tungsten oxide electrochromic and energy storage material according to claim 1, characterized in that the electrochromic and energy storage material has electrochromic properties and can realize a macroscopically rapid reversible change between transparent and dark blue, the coloration time is 0.9-2.8s, the bleaching time is 2.5-4.8s, and no attenuation occurs for cycles exceeding 6000 cycles.

3. The electrochromic and energy-storage material of vanadium-doped monocrystalline tungsten oxide as claimed in claim 1, wherein the electrochromic and energy-storage material is responsive to the storage and release of electric quantity during the electrochromic fading process, and has a capacitance of 20-50mF/cm²And has rate capability.

4. The method for preparing the vanadium-doped single-crystal tungsten oxide electrochromic and energy storage material according to any one of claims 1 to 3, which is characterized by comprising the following steps:

s1, ultrasonically cleaning the FTO substrate by using ethanol and deionized water respectively, and then drying in a drying oven;

s2, placing the FTO substrate dried in the step S1 into a magnetron sputtering vacuum chamber, and pumping to 2 x 10^-4Introducing argon-oxygen mixed gas, performing radio frequency magnetron deposition reaction on the surface of the substrate, depositing a tungsten oxide seed crystal layer, and then performing annealing treatment;

s3, adding tungstic acid powder, deionized water and hydrogen peroxide into the beaker I, heating and stirring until the mixture is clear to obtain 0.01-0.1mol/l of peroxytungstic acid;

s4, adding vanadium pentoxide powder, deionized water and hydrogen peroxide into the beaker II, and stirring in an ice bath until the mixture is clear to obtain 0.01-0.1mol/l of peroxyvanadic acid;

s5, mixing the solutions obtained in the step S3 and the step IV S4 according to the atomic ratio of 0-5 percent of vanadium to tungsten; sequentially adding deionized water, a mixed solution of peroxytungstic acid and peroxyvanadic acid, hydrochloric acid and acetonitrile into a beaker III, and stirring for 5-10min to obtain a precursor solution;

s6, obliquely placing the FTO substrate processed in the step S2 into a reaction kettle filled with the precursor solution in the step S5, placing the reaction kettle into an oven for heating, and naturally cooling to room temperature;

and S7, cleaning the product obtained in the step S6 by deionized water, and carrying out annealing treatment to obtain the vanadium-doped single-crystal tungsten oxide electrochromic and energy storage material.

5. The method for preparing the vanadium-doped single-crystal tungsten oxide electrochromic and energy storage material according to claim 4, wherein the method comprises the following steps: the specific process of step S1 is: and ultrasonically cleaning the FTO substrate by using ethanol and deionized water for 30-40min in sequence, and then drying in a drying oven.

6. The method for preparing the vanadium-doped single-crystal tungsten oxide electrochromic and energy storage material according to claim 4, wherein the method comprises the following steps: in the step S2, the target material for the radio frequency magnetron deposition is tungsten trioxide with the purity of 99.999%, and the ratio of argon to oxygen is (0.5-5): 1, sputtering with the pressure of 0.5-2.5pa, the sputtering power of 20-40W and the sputtering time of 5-15 min; the annealing temperature is 350-450 ℃, the heating rate is 2-5 ℃/min, and the heat preservation time is 1-2 h.

7. The method for preparing the vanadium-doped single-crystal tungsten oxide electrochromic and energy storage material according to claim 4, wherein the method comprises the following steps: in step S3, the volume ratio of hydrogen peroxide to deionized water is 1:3, and the stirring temperature is 80-100 ℃.

8. The method for preparing the vanadium-doped single-crystal tungsten oxide electrochromic and energy storage material according to claim 4, wherein the method comprises the following steps: in the step S4, the volume ratio of the hydrogen peroxide to the deionized water is 3:1, the hydrogen peroxide is added in two times, and the stirring temperature is 0-10 ℃.

9. The method for preparing the vanadium-doped single-crystal tungsten oxide electrochromic and energy storage material according to claim 4, wherein the method comprises the following steps: in step S5, the volume ratio of deionized water, the mixed solution of peroxytungstic acid and peroxyvanadic acid, and acetonitrile is 4:3: 2.

10. The method for preparing the vanadium-doped single-crystal tungsten oxide electrochromic and energy storage material according to claim 4, wherein the method comprises the following steps: in the step S6, the heating and heat preservation temperature of the oven is 150-; in step S7, the annealing temperature is 150-.

Technical Field

The invention relates to the technical field of functional thin film materials, in particular to a vanadium-doped monocrystalline tungsten oxide electrochromic energy storage material and a preparation method thereof.

Background

Electrochromism refers to the optical properties of an electroactive material, including the phenomenon that the transmittance, reflectance, color, and the like of the material reversibly change under an alternating low electric field. The device can intelligently control color change, and reduce energy required for keeping temperature by effectively absorbing or reflecting external radiation and internal heat diffusion, so that the device is widely applied to equipment such as mobile phone backshells and intelligent windows. Among a plurality of electrochromic materials, tungsten oxide has a high optical modulation rate, pure color change (from colorless transparency to dark blue), and good ultraviolet resistance, and is the most widely studied material. It is now widely believed that the electrochromic properties and crystallinity of tungsten oxide are strongly correlated, wherein amorphous (amorphous) tungsten oxide has a fast response time and high coloring efficiency due to a large number of polygonal channels in its structure. Crystalline tungsten oxide is dense in structure, but has narrow ion intercalation channels, only small cation intercalation, slow response time and low coloring efficiency. Therefore, it is of great research significance to improve the electrochromic performance of the crystalline tungsten oxide film.

Disclosure of Invention

The invention aims to: provides a vanadium doped single crystal tungsten oxide electrochromic and energy storage material and a preparation method thereof, aiming at solving the defects.

In order to achieve the above purpose, the invention provides the following technical scheme:

the electrochromic and energy-storing material has porous monocrystal nanometer line structure with nanometer rod diameter of 15-40nm and directionally grown nanometer line with vanadium doped homogeneously in the nanometer line.

Preferably, the electrochromic and energy storage material has electrochromic properties, can realize rapid reversible change between transparent and dark blue on a macroscopic scale, has coloring time of 0.9-2.8s, fading time of 2.5-4.8s and cycle number of more than 6000 circles, and does not decay.

Preferably, the electrochromic and energy storage material simultaneously stores and releases corresponding electric quantity in the electrochromic fading process, and the electric capacity is 20-50mF/cm²And has rate capability.

Preferably, the preparation method of the vanadium-doped single-crystal tungsten oxide electrochromic and energy storage material specifically comprises the following steps:

s1, ultrasonically cleaning the FTO substrate by using ethanol and deionized water respectively, and then drying in a drying oven;

s2, placing the FTO substrate dried in the step S1 into a magnetron sputtering vacuum chamber, and pumping to 2 x 10^-4Introducing argon-oxygen mixed gas, performing radio frequency magnetron deposition reaction on the surface of the substrate, depositing a tungsten oxide seed crystal layer, and then performing annealing treatment;

s3, adding tungstic acid powder, deionized water and hydrogen peroxide into the beaker I, heating and stirring until the mixture is clear to obtain 0.01-0.1mol/l of peroxytungstic acid;

s4, adding vanadium pentoxide powder, deionized water and hydrogen peroxide into the beaker II, and stirring in an ice bath until the mixture is clear to obtain 0.01-0.1mol/l of peroxyvanadic acid;

s5, mixing the solutions obtained in the step S3 and the step IV S4 according to the atomic ratio of 0-5 percent of vanadium to tungsten; sequentially adding deionized water, a mixed solution of peroxytungstic acid and peroxyvanadic acid, hydrochloric acid and acetonitrile into a beaker III, and stirring for 5-10min to obtain a precursor solution;

s6, obliquely placing the FTO substrate processed in the step S2 into a reaction kettle filled with the precursor solution in the step S5, placing the reaction kettle into an oven for heating, and naturally cooling to room temperature;

and S7, cleaning the product obtained in the step S6 by deionized water, and carrying out annealing treatment to obtain the vanadium-doped single-crystal tungsten oxide electrochromic and energy storage material.

Preferably, the specific process of step S1 is: and ultrasonically cleaning the FTO substrate by using ethanol and deionized water for 30-40min in sequence, and then drying in a drying oven.

Preferably, in step S2, the rf magnetron deposition reaction uses a tungsten trioxide target with a purity of 99.999%, and the ratio of argon to oxygen is (0.5-5): 1, sputtering with the pressure of 0.5-2.5pa, the sputtering power of 20-40W and the sputtering time of 5-15 min; the annealing temperature is 350-450 ℃, the heating rate is 2-5 ℃/min, and the heat preservation time is 1-2 h.

Preferably, in step S3, the volume ratio of hydrogen peroxide to deionized water is 1:3, and the stirring temperature is 80-100 ℃.

Preferably, the volume ratio of the hydrogen peroxide to the deionized water in the step S4 is 3:1, the hydrogen peroxide is added in two times, and the stirring temperature is 0-10 ℃.

Preferably, in step S5, the volume ratio of the deionized water, the mixed solution of peroxytungstic acid and peroxyvanadic acid, and the acetonitrile is 4:3: 2.

Preferably, in step S6, the temperature of oven heating and heat preservation is 150-; in step S7, the annealing temperature is 150-.

The invention has the beneficial effects that:

the vanadium-doped single-crystal tungsten oxide electrochromic and energy storage material is a porous single-crystal nanowire array structure, is large in specific surface area and short in ion diffusion path, and can effectively improve the speed of electron transmission and ion diffusion and improve the response speed of a bifunctional material. The deep blue and transparent conversion can be rapidly carried out under different voltages, and the storage and the release of the corresponding electric quantity can be realized, so that the energy-saving color-changing lens can be applied to the fields of energy-saving color-changing lenses, mobile phone back plates, energy-saving windows, intelligent display and the like.

According to the preparation method of the vanadium-doped single-crystal tungsten oxide electrochromic and energy storage material, chemical properties of a tungsten source precursor and a vanadium source precursor are matched, peroxyvanadic acid is used as a doping source, the chemical properties of peroxytungstic acid are closer to those of peroxyvanadic acid, the doping amount can be accurately controlled, and the response rate can be doubled under the condition that the doping amount of vanadium is 0.1% and low in doping amount. By doping vanadium, the crystal face spacing is enlarged, the oxygen vacancy content is improved, vanadium-oxygen bonds are formed, the ion diffusion speed is further improved, the reaction kinetic process is accelerated, the response rate and the electrochromic performance are improved, and the super-capacitor performance is obtained to achieve the energy storage effect.

Drawings

FIG. 1: an electron microscope scanning image of the vanadium doped single crystal tungsten oxide electrochromic and energy storage material prepared in the embodiment 1 of the invention;

FIG. 2: the transmission electron microscope high resolution image of the vanadium doped single crystal tungsten oxide electrochromic and energy storage material prepared in the embodiment 1 of the invention;

FIG. 3: according to the invention, the transmission electron microscope dark field image and the electron energy spectrogram of the vanadium-doped single-crystal tungsten oxide electrochromic and energy storage material prepared in the embodiment 1 are shown in the specification;

FIG. 4: the electrochromic property of the vanadium-doped single-crystal tungsten oxide prepared in the embodiment 1 of the invention and the kinetic transmittance at 633nm of the energy storage material are shown in the figure;

FIG. 5: an x-ray photoelectron energy spectrum of the vanadium-doped single-crystal tungsten oxide electrochromism and energy storage material prepared in the embodiment 2 of the invention;

FIG. 6: the vanadium-doped single-crystal tungsten oxide electrochromic and energy storage material prepared in the embodiment 2 of the invention has a constant-current charge-discharge curve and an in-situ transmittance curve corresponding to 633 nm.

Detailed Description

The present invention is further described with reference to the following examples, which are intended to be illustrative and illustrative only, and various modifications, additions and substitutions for the specific embodiments described herein may be made by those skilled in the art without departing from the spirit of the invention or exceeding the scope of the claims.

Example 1:

a preparation method of a vanadium-doped single-crystal tungsten oxide electrochromic and energy storage material specifically comprises the following steps:

s1, the FTO (F-doped coated conductive glass) substrate was ultrasonically cleaned with ethanol and deionized water, respectively, for 30min in sequence, followed by drying in a drying oven.

S2, putting the FTO substrate dried in the step S1 into a magnetron sputtering vacuum chamber by using a tungsten trioxide target material with the purity of 99.999 percent, and pumping to 2 x 10^-4Pa, introducing argon-oxygen mixed gas, wherein the ratio of argon to oxygen is 1: 1, sputtering at 0.8pa under 30W for 10min, performing radio frequency magnetron deposition reaction on the surface of a substrate, and depositing a tungsten oxide seed crystal layer; and then putting the substrate into a tube furnace for annealing treatment, wherein the annealing temperature is 400 ℃, the heating rate is 3.3 ℃/min, and the heat preservation time is 2h, so as to obtain a seed crystal layer of the layer crystal state tungsten oxide.

S3, adding 0.25g of tungstic acid powder, 60ml of deionized water and 20ml of hydrogen peroxide into the beaker I, heating to 95 ℃, and stirring until the mixture is clear to obtain 0.05mol/l of peroxytungstic acid.

S4, adding 0.45g of vanadium pentoxide powder, 10ml of deionized water and 30ml of hydrogen peroxide into a beaker II, adding the hydrogen peroxide twice, adding ice water, adjusting the temperature to 0 ℃, carrying out ice bath, and stirring until the mixture is clear, thereby obtaining 0.05mol/l of peroxyvanadic acid.

S5, mixing the solutions obtained in the step S3 and the step IV S4 according to the atomic ratio of 0.1 percent of vanadium to tungsten; and sequentially adding 28ml of deionized water, 21ml of a mixed solution of peroxytungstic acid and peroxyvanadic acid, 3.5ml of hydrochloric acid and 14ml of acetonitrile into a beaker III, and stirring for 10min to obtain a precursor solution.

S6, obliquely placing the FTO substrate processed in the step S2 into a reaction kettle filled with the precursor solution in the step S5, placing the reaction kettle into an oven for heating, keeping the temperature of the oven at 180 ℃ for 12 hours, and naturally cooling to room temperature.

And S7, cleaning the product obtained in the step S6 by using deionized water, and carrying out annealing treatment, wherein the annealing temperature is 200 ℃, the heating rate is 3.3 ℃/min, and the heat preservation time is 1h, so that the vanadium-doped single crystal tungsten oxide electrochromic and energy storage material is obtained.

Example 2:

a preparation method of a vanadium-doped single-crystal tungsten oxide electrochromic and energy storage material specifically comprises the following steps:

s1, the FTO (F-doped coated conductive glass) substrate was ultrasonically cleaned with ethanol and deionized water, respectively, for 30min in sequence, followed by drying in a drying oven.

S2, putting the FTO substrate dried in the step S1 into a magnetron sputtering vacuum chamber by using a tungsten trioxide target material with the purity of 99.999 percent, and pumping to 2 x 10^-4Pa, introducing argon-oxygen mixed gas, wherein the ratio of argon to oxygen is 1: 1, sputtering at 0.8pa under 30W for 10min, performing radio frequency magnetron deposition reaction on the surface of a substrate, and depositing a tungsten oxide seed crystal layer; and then putting the substrate into a tube furnace for annealing treatment, wherein the annealing temperature is 400 ℃, the heating rate is 3.3 ℃/min, and the heat preservation time is 2h, so as to obtain a seed crystal layer of the layer crystal state tungsten oxide.

S3, adding 0.25g of tungstic acid powder, 60ml of deionized water and 20ml of hydrogen peroxide into the beaker I, heating to 95 ℃, and stirring until the mixture is clear to obtain 0.05mol/l of peroxytungstic acid.

S4, adding 0.45g of vanadium pentoxide powder, 10ml of deionized water and 30ml of hydrogen peroxide into a beaker II, adding the hydrogen peroxide twice, adding ice water, adjusting the temperature to 0 ℃, carrying out ice bath, and stirring until the mixture is clear, thereby obtaining 0.05mol/l of peroxyvanadic acid.

S5, mixing the solutions obtained in the step S3 and the step IV S4 according to the atomic ratio of 0.5 percent of vanadium to tungsten; and sequentially adding 28ml of deionized water, 21ml of a mixed solution of peroxytungstic acid and peroxyvanadic acid, 3.5ml of hydrochloric acid and 14ml of acetonitrile into a beaker III, and stirring for 10min to obtain a precursor solution.

S6, obliquely placing the FTO substrate processed in the step S2 into a reaction kettle filled with the precursor solution in the step S5, placing the reaction kettle into an oven for heating, keeping the temperature of the oven at 180 ℃ for 12 hours, and naturally cooling to room temperature.

And S7, cleaning the product obtained in the step S6 by using deionized water, and carrying out annealing treatment, wherein the annealing temperature is 200 ℃, the heating rate is 3.3 ℃/min, and the heat preservation time is 1h, so that the vanadium-doped single crystal tungsten oxide electrochromic and energy storage material is obtained.

Example 3:

a preparation method of a vanadium-doped single-crystal tungsten oxide electrochromic and energy storage material specifically comprises the following steps:

s1, the FTO (F-doped coated conductive glass) substrate was ultrasonically cleaned with ethanol and deionized water, respectively, for 40min in sequence, followed by drying in a drying oven.

S2, putting the FTO substrate dried in the step S1 into a magnetron sputtering vacuum chamber by using a tungsten trioxide target material with the purity of 99.999 percent, and pumping to 2 x 10^-4Pa, introducing argon-oxygen mixed gas, wherein the ratio of argon to oxygen is 5: 1, sputtering at 2.5pa under 20W for 15min, performing radio frequency magnetron deposition reaction on the surface of a substrate, and depositing a tungsten oxide seed crystal layer; and then putting the substrate into a tube furnace for annealing treatment, wherein the annealing temperature is 450 ℃, the heating rate is 5 ℃/min, and the heat preservation time is 1h, so as to obtain a seed crystal layer of the layer-crystalline tungsten oxide.

S3, adding 0.05g of tungstic acid powder, 15ml of deionized water and 5ml of hydrogen peroxide into the beaker I, wherein the volume ratio of the hydrogen peroxide to the deionized water is 1:3, heating to 100 ℃, and stirring until the mixture is clear to obtain 0.1mol/l of peroxytungstic acid.

S4, adding 0.09g of vanadium pentoxide powder, 2ml of deionized water and 6ml of hydrogen peroxide into a beaker II, wherein the volume ratio of the hydrogen peroxide to the deionized water is 3:1, adding the hydrogen peroxide twice, adding ice water, adjusting the temperature to 10 ℃, carrying out ice bath, and stirring until the mixture is clear, thereby obtaining 0.01mol/l of peroxyvanadic acid.

S5, mixing the solutions obtained in the step S3 and the step IV S4 according to the vanadium-tungsten atomic ratio of 5 percent; and sequentially adding 28ml of deionized water, 21ml of a mixed solution of peroxytungstic acid and peroxyvanadic acid, 3.5ml of hydrochloric acid and 14ml of acetonitrile into a beaker III, and stirring for 5min to obtain a precursor solution.

S6, obliquely placing the FTO substrate processed in the step S2 into a reaction kettle filled with the precursor solution in the step S5, placing the reaction kettle into an oven for heating, keeping the temperature of the oven at 150 ℃, keeping the temperature for 10 hours, and naturally cooling to room temperature.

And S7, cleaning the product obtained in the step S6 by using deionized water, and carrying out annealing treatment, wherein the annealing temperature is 250 ℃, the heating rate is 5 ℃/min, and the heat preservation time is 1.5h, so that the vanadium-doped single-crystal tungsten oxide electrochromic and energy storage material is obtained.

Example 4:

a preparation method of a vanadium-doped single-crystal tungsten oxide electrochromic and energy storage material specifically comprises the following steps:

s1, the FTO (conductive glass coated with the doped F) substrate is sequentially and respectively cleaned by ethanol and deionized water for 30-40min in an ultrasonic mode, and then dried in a drying oven.

S2, putting the FTO substrate dried in the step S1 into a magnetron sputtering vacuum chamber by using a tungsten trioxide target material with the purity of 99.999 percent, and pumping to 2 x 10^-4Pa, introducing argon-oxygen mixed gas, wherein the ratio of argon to oxygen is 0.5: 1, sputtering at 0.5pa under 40W for 5min, performing radio frequency magnetron deposition reaction on the surface of a substrate, and depositing a tungsten oxide seed crystal layer; and then putting the substrate into a tube furnace for annealing treatment, wherein the annealing temperature is 350 ℃, the heating rate is 2 ℃/min, and the heat preservation time is 2h, so as to obtain a seed crystal layer of the layer-crystalline tungsten oxide.

S3, adding 0.5g of tungstic acid powder, 120ml of deionized water and 40ml of hydrogen peroxide into the beaker I, wherein the volume ratio of the hydrogen peroxide to the deionized water is 1:3, heating to 80 ℃, and stirring until the mixture is clear to obtain 0.01mol/l of peroxytungstic acid.

S4, adding 0.9g of vanadium pentoxide powder, 20ml of deionized water and 60ml of hydrogen peroxide into a beaker II, wherein the volume ratio of the hydrogen peroxide to the deionized water is 3:1, adding the hydrogen peroxide twice, adding ice water, adjusting the temperature to 5 ℃, carrying out water bath, and stirring until the mixture is clear, thereby obtaining 0.1mol/l of peroxyvanadic acid.

S5, mixing the solutions obtained in the step S3 and the step IV S4 according to the vanadium-tungsten atomic ratio of 5 percent; and sequentially adding 28ml of deionized water, 21ml of a mixed solution of peroxytungstic acid and peroxyvanadic acid, 3.5ml of hydrochloric acid and 14ml of acetonitrile into a beaker III, and stirring for 5min to obtain a precursor solution.

S6, obliquely placing the FTO substrate processed in the step S2 into a reaction kettle filled with the precursor solution in the step S5, placing the reaction kettle into an oven for heating, keeping the temperature of the oven at 180 ℃ for 6 hours, and naturally cooling to room temperature.

And S7, cleaning the product obtained in the step S6 by using deionized water, and carrying out annealing treatment, wherein the annealing temperature is 150 ℃, the heating rate is 2 ℃/min, and the heat preservation time is 2h, so that the vanadium-doped single crystal tungsten oxide electrochromic and energy storage material is obtained.

The vanadium-doped single-crystal tungsten oxide electrochromic and energy storage materials prepared in the embodiments 1 to 4 are all porous single-crystal nanowire array structures, have large specific surface areas and short ion diffusion paths, and can effectively improve the speed of electron transmission and ion diffusion and improve the response speed of the bifunctional material. The deep blue and transparent conversion can be rapidly carried out under different voltages, and the storage and the release of the corresponding electric quantity can be realized, so that the energy-saving color-changing lens can be applied to the fields of energy-saving color-changing lenses, mobile phone back plates, energy-saving windows, intelligent display and the like.

According to the preparation method of the vanadium-doped single-crystal tungsten oxide electrochromic and energy storage material in the embodiment 1-4, through matching the chemical properties of the tungsten source and the vanadium source precursor, the peroxovanadic acid is used as a doping source, the chemical properties of the peroxovanadic acid are closer to those of the peroxotungstic acid, the doping amount can be accurately controlled, and the response rate can be doubled under the condition that the vanadium doping amount is 0.1% and low in doping. By doping vanadium, the crystal face spacing is enlarged, the oxygen vacancy content is improved, vanadium-oxygen bonds are formed, the ion diffusion speed is further improved, the reaction kinetic process is accelerated, the response rate and the electrochromic performance are improved, and the super-capacitor performance is obtained to achieve the energy storage effect.

Taking example 1 as an example, the electrochromic and energy storage material of vanadium-doped single-crystal tungsten oxide prepared in this example is detected by an electron microscope, a transmission electron microscope, and the like, as shown in fig. 1-4, fig. 1 is an electron microscope scanning image of the electrochromic and energy storage material of vanadium-doped single-crystal tungsten oxide prepared in this example, fig. 2 is a transmission electron microscope high resolution image of the electrochromic and energy storage material of vanadium-doped single-crystal tungsten oxide prepared in this example, fig. 3 is a transmission electron microscope dark field image and an electronic energy spectrum of the electrochromic and energy storage material of vanadium-doped single-crystal tungsten oxide prepared in this example, and fig. 4 is a dynamic transmittance image at 633nm of the electrochromic and energy storage material of vanadium-doped single-crystal tungsten oxide prepared in this example.

As can be seen from fig. 1 to 3, nanowires growing upward are prepared with uniform distribution, the diameter of the nanowires is 15 to 40nm, the high resolution picture of fig. 2 shows a larger interplanar spacing in the direction of nanowire growth (002), and elemental analysis of fig. 3 shows that vanadium is successfully and uniformly doped in tungsten oxide nanowires. As can be seen from FIG. 4, from the dynamics, the contrast ratio of the prepared vanadium doped single crystal tungsten oxide electrochromic and energy storage material is 84.9%, the fading time is 2.5s, and the coloring time is 0.9 s.

Taking the example 2 as an example, the vanadium-doped single-crystal tungsten oxide electrochromic and energy storage material prepared in the example is subjected to x-ray photoelectron spectrogram and constant-current charge-discharge detection. 5-6, FIG. 5 is an x-ray photoelectron spectrum of the electrochromic and energy storage material of vanadium doped single crystal tungsten oxide prepared in the example of the present invention; FIG. 6 is a constant current charge-discharge curve and a corresponding in-situ transmittance curve at 633nm of the vanadium-doped single-crystal tungsten oxide electrochromic and energy storage material prepared in the embodiment of the present invention.

It can be seen from FIG. 5 that the vanadium-oxygen bond is formed, the higher oxygen vacancy content; from the constant current charge-discharge curve and the corresponding in-situ transmittance curve of the vanadium-doped single-crystal tungsten oxide electrochromic and energy storage material in FIG. 6, it can be seen that the surface capacitance is as high as 47.04mF/cm²。

The vanadium-doped single-crystal tungsten oxide electrochromic and energy storage material has a porous single-crystal nanowire structure, the diameter of a nanorod is 15-40nm, the nanowire grows directionally, and vanadium is uniformly doped in the nanowire. By way of examples 1 to 4 anda large amount of experimental data show that the electrochromic and energy storage material has electrochromic performance, can realize rapid reversible change between transparent and dark blue on a macroscopic scale, has coloring time of 0.9-2.8s, fading time of 2.5-4.8s and cycle number of more than 6000 circles, and does not generate obvious attenuation. And in the electrochromism fading process, the capacitance is 20-50mF/cm corresponding to the storage and release of electric quantity²And has rate capability.

The invention relates to a preparation method of a vanadium-doped single-crystal tungsten oxide electrochromic and energy storage material, which is characterized in that magnetron-sputtered tungsten oxide nano particles are used as seed crystal layers and are directionally grown by combining a hydrothermal method to obtain vanadium-doped tungsten oxide nano wires with a close-packed hexagonal structure.

The foregoing is an illustrative description of the invention, and it is clear that the specific implementation of the invention is not restricted to the above-described manner, but it is within the scope of the invention to apply the inventive concept and solution to other applications without substantial or direct modification.